This invention generally relates to a carton flap folding assembly and methods for use in a continuous motion packaging machine for packaging articles such as, for example, beverage containers. This invention also includes the methods of folding carton flaps. This invention is particularly suitable for folding the gussets of a carton flap of a wrap-around type carton as the carton is being wrapped around a preformed bottle group in a continuous motion packaging machine. The present invention also includes a packaging machine utilizing the improved carton flap folding methods and apparatus disclosed.
Continuous motion article packaging machines, such as those used in the beverage packaging industry are well known, and various types of packaging machines are constructed to accomplish the packaging of articles into different types of cartons. One such machine enables articles, such as glass or plastic bottles, to be packaged in a wrap-around paperboard carton. For example, Riverwood International Corporation""s Marksman(trademark) series of packaging machines are specifically designed to package beverage containers into a wrap-around type carton. These various types of Marksman(trademark) packaging machines include sequential work stations in which the cartons and/or the bottle groups are placed in a proper orientation or configuration, and the packaging process is accomplished in high speed, continuous fashion. These known machines include a carton feeding magazine or feeder that selects a single paperboard carton blank and transfers that carton blank to an infeed area where the carton is moved, still in its blank or unfolded state into position to be placed over a preformed bottle group. The carton blank is moved downstream being supported in a horizontal position by an upstream plow. As the carton blank continues to be moved through the machine, its front side panels are plowed downwardly to fold around the bottle group as the bottle group continues to move in a downstream direction, through the machine. As the carton is continuously and sequentially folded around the bottle group, the opposing end sections of the carton blank, which become the bottom portions of the completely folded carton, come in contact with one another and typically are glued or locked into position to complete the preformed carton. During the process of folding the carton blank around the preformed bottle group, however, there is typically other carton flap folding steps which must take place simultaneously with the carton side flap folding, in order to result in a completely folded carton around the bottle group.
The carton includes flaps that, in their folded state, comprise panels which not only assist in holding the bottle group in place in a fully formed carton, but also provide a surface onto which graphics, such as advertising, can be placed. These flaps are commonly referred to as advertising panels or xe2x80x9cad panels.xe2x80x9d Such ad panels are well known and include a central, flat section and opposed side webs or gussets that effectively connect the central section to the carton blank at its edges. The central section also is connected to the carton blank along a third side edge.
It also is known in the art that these gussets must be folded inwardly, toward the interior portion of the carton as the carton side panels are folded around the bottle group, in order to permit the ad panels to be properly oriented vertically in a filly formed carton. Therefore, two gussets are associated with each ad panel, with the first ad panel being positioned along the upper, leading side of the carton and a second ad panel being positioned along the upper, trailing side of a carton as the carton passes in the downstream or feed direction of the machine. The gussets include a fold line which facilitates the folding of the ad panel downwardly and the folding of the respective gusset inwardly. The necessity to fold the gussets inwardly, however, also necessitates that a separate apparatus be included along with the packaging machine at the folding workstation to affirmatively contact the gusset and fold the gusset inwardly along its fold line. Known prior gusset folding devices include-stationary plows which are placed in the feed path of the carton at the position of the gusset fold line, which simply push the gusset inwardly as the carton is affirmatively moved in its downstream direction, to fold the gussets attached to the leading ad panel. It has proved more difficult, however, to fold the gussets of the trailing ad panel, considering that the trailing ad panel is moving in the downstream direction along with the carton blank away from a trailing or upstream folding device. This required the use of moving components to track the downstream motion of the carton blank for a specified distance, and articulate projections such as fingers against the gussets to move the trailing gussets inwardly.
It is also known in the art to provide overhead paddles on a moving belt that tracks the carton blank movement to fold the ad panels into a horizontal position, as the known gusset folding devices push the gussets inwardly toward the interior of the carton. These articulating gusset folding devices include tucking fingers that are carried by a chain driven around an outer camming surface or cam track. An inner cam track is utilized to articulate the folding fingers at the appropriate position in order to move the fingers against the trailing gussets as the trailing gussets move in the downstream direction as the carton side flaps are folded downwardly. This entire device typically is in the form of a cassette, which can be placed into proper position, and is associated with a particular sized bottle group and machine pitch. If the packaging machine was run on a different pitch, requiring a different bottle group configuration and a different carton, the cassette could be removed and replaced with another cassette specifically designed for that machine pitch.
These gusset-folding cassettes, however, include a number of disadvantages. First, the gusset-folding cassettes are extremely heavy and difficult to install, thus increasing change-over time between various product runs which lowers productivity. Second, the gusset-folding cassettes have a large number of parts, making them difficult and expensive to build and maintain. Additionally, due to the complex nature of the gusset-folding cassettes, malfunctions sometimes occur when running the continuous packaging machine a high rate of speed, which creates machine down-time, lowers productivity and increases manufacturing costs.
The present invention relates to a continuous motion article packaging machine of the type having an article transport conveyor for moving a pre-configured group of articles through the machine and for packaging the article group into a paperboard carton. More specifically, the present invention relates to a carton folding assembly, which includes a tucker wheel for tucking a gusset which connects the folding flap to main sections of the carton. In the preferred embodiment, the tucker wheel is vertically oriented just above a main transport conveyor within the machine and includes first and second engagement surfaces. The preferred embodiment includes an assembly mechanically attached to the tucker wheel for rotating the tucker wheel so that the first engaging surface contacts the first portion of the carton and a second engaging surface contacts a second portion of the carton.
In the preferred embodiment, a circumferential edge portion of the tucker wheel actually comprises the first engagement surface. Additionally, in the preferred embodiment of the present invention, the tucker wheel includes a notch formed into the outer periphery of the tucker wheel. The notch is comprised of a depressed portion defined by a space between a leading tooth and a trailing tooth. In the preferred embodiment, the trailing tooth comprises the second engaging surface.
In a preferred embodiment of the present invention the tucker wheel assembly may also include a tucker wheel arm having a first end for rotatably supporting the tucker wheel and a second end which is rotatably fastened to a portion of the article packaging machine frame, so that the tucker wheel arm may rotate into a first position to engage the carton flaps within cartons translating downstream the packaging machine. Additionally, the tucker wheel arm may then rotate into a second position to effectively remove the carton flap folding assembly away from cartons translating downstream. This feature allows the removal of the tucker wheel assembly for machine maintenance or product changeover. The carton flap folding assembly may also include a height adjustment mechanism for allowing an adjustment of a height of the tucker wheel with respect to the conveyor for accommodating articles of varying heights. In a preferred embodiment, the tucker wheel circumferal edge is located just below the planar surface of the carton so as to engage a carton flap after it is folded into a vertical position below a planar surface of the carton. In a preferred embodiment of the present invention, the machine may also include an upper conveyor for conveying carton blanks from a carton magazine to the carton flap folding assembly. The upper conveyor may include paddles for contacting the carton flaps and for moving the carton flaps into a substantially perpendicular orientation with respect to a horizontal axis of the carton. Additionally, the first and second engagement surfaces may then contact and the fold gussets beneath the carton. More specifically, the first engagement surface on the tucker wheel contacts gussets attached to a first flap on a leading edge portion of a carton progressing through the machine, and the second engagement surface comprises a trailing edge tooth defined by the notch for contacting gussets attached to the second flap on a trailing portion of the carton as it progresses through the machine. Finally, the invention may also include a pair of tucker wheels separated by a predetermined space for simultaneously contacting gussets on lateral edges of the carton flaps.
The present invention also relates to an improved method for folding a carton flap within a paperboard carton prior to wrapping the paperboard carton around a pre-configured group of articles wherein the method comprises the steps of disposing the carton tucking wheel adjacent to a transportant conveyor, wherein the carton tucking wheel includes first and second engaging surfaces, engaging a paperboard carton at a first portion by the first engaging surface to fold a portion of the carton away from the first engaging surface and engaging a second portion of the carton by the second engaging surface to fold the second portion of the carton away from the second engaging surface.
In a preferred embodiment of the present invention the method may also include the step of engaging the first carton portion with a substantially circumferential edge portion of the tucker wheel. Additionally, the improved method may include the step of engaging the second portion of the carton with a trailing tooth to disposed on the tucker wheel. Finally, the inventive method may also include the step of utilizing a pair of tucker wheels to contact gussets disposed on lateral portions of each folding flap within a carton.
These and other features of the present invention will become apparent upon reading the following specification when taken in conjunction with the accompanying drawings.